Abstract: A data compression system and method for that is capable of detecting and eliminating repeated phrases of variable length within a window of virtually unlimited size.

Abstract: Path determination constraints may be encoded in the form of a program having one or more instructions. Each of instructions may include an operation code, and operands (or pointers to locations where operands are stored). In this way, an extensible, interoperable way for a nodes (e.g., label-switching routers) to communicate constraints within a network is provided. Such constraints may be inserted (e.g., as one or more CONSTRAINT objects) into signaling messages (e.g., a PATH RSVP message). By enabling the signaling of constraints, the determination of constraint-based (label-switched) paths can be distributed among a number of (label-switching) routers or other nodes. Upon receiving a message with constraints (e.g.

Abstract: A virtual routing system includes a number of physical routers. One of the physical routers is the master with respect to a given source of traffic, and the others are backups. If the master router fails, then one of the backup routers becomes the master to provide substantially uninterrupted service through the virtual routing system. A virtual redundant routing protocol (VRRP) can be extended to support sub-second advertising of VRRP packets by a master router a backup router. In some cases, sub-second switching is supported, in which a backup router can become a new master router after less than a second of down time by the original master router. Such responsiveness in a virtual routing system is very useful for many applications, such as voice-over-packet applications in which down time of the routing system for more than one second is unacceptable.

Abstract: A network device includes one or more processing units and an external memory. Each of the one or more processing units includes a centralized counter configured to perform accounting for the respective processing unit. The external memory is associated with at least one of the one or more processing units and is configured to store a group of count values for the at least one processing unit.

Abstract: A network device includes a memory and a packet forwarding engine. The memory stores a multicast list table, tag descriptor data and layer 2 (L2) encapsulation data. The packet forwarding engine receives a first pointer to an entry in the multicast list table, the entry including a second pointer to the tag descriptor data. The packet forwarding engine utilizes the second pointer to retrieve the tag descriptor data, the tag descriptor data including a third pointer to the encapsulation data. The packet forwarding engine constructs a packet header utilizing the retrieved encapsulation data and appends the packet header to a packet payload for forwarding out of the packet forwarding engine.

Abstract: The invention is directed to techniques for supporting multi-link protocols within a computer network. In one embodiment, a method includes receiving a set of data blocks from a plurality of links in one or more interface cards according to a multi-link protocol and sending the data blocks to a multi-link service card for sequencing. The data blocks may then be sent to the one or more interface cards for communication to a destination device over a computer network. Implementing a multi-link service card may allow a network device, such as a router, to support multi-link protocols.

Abstract: A network device integrates accounting functionality for generation of flow statistics with packet intercept functionality to provide a comprehensive traffic analysis environment. The device comprises a set of network interface cards to receive packets from a network, and a set of accounting service cards to calculate flow statistics for the packets. The device further comprises a control unit to receive the network packets from the interface cards and distribute the packets to the set of accounting service cards. The accounting service card comprises an interface for insertion within a slot of a network device. Accounting service cards may be added to easily scale the network device to support higher bandwidth communication links, such as OC-3, OC-12, OC048 and higher rate links. Additional accounting service cards may be used for purposes of redundancy to support continuous, uninterrupted packet processing and accounting in the event of a card failure.

Abstract: Techniques are described for managing periodic communications between devices. For example, a periodic packet process may receive configuration parameters from a routing protocol process. The periodic packet process may manage periodic communication sessions with neighboring devices in accordance with the configuration parameters from the routing protocol process. The periodic packet process may monitor for incoming periodic packets from a specified neighboring device in a specified periodic time interval. The periodic packet process may also send outbound periodic packets at a specified periodic time interval.

Abstract: A method of scheduling upstream bandwidth. This method comprises: 1) anticipating the need for the upstream bandwidth in advance of any specific request for said upstream bandwidth; and 2) scheduling the upstream bandwidth in accordance with such need.

Abstract: A hierarchical traffic policer may include a first policer configured to pass first packets when a first condition is met. The first policer also may alter selection information within the passed first packets. A second policer may be configured to pass second packets when a second condition is met. The second policer may be further configured to pass all of the passed first packets from the first policer based on the altered selection information within the passed first packets.

Abstract: A system, method, and device for computer networking. According to one embodiment of the invention, the method includes receiving from a remote client a request for a web resource containing renderable and non-renderable data. The method further includes filtering at least a portion of the non-renderable data from the requested web resource, thereby creating a modified web resource. The method also includes sending the modified web resource to the remote client. Non-renderable data may include whitespace, comments, hard returns, meta tags, keywords, or other data not used by a browser to present a web page.

Abstract: A network content service apparatus includes a set of compute elements adapted to perform a set of network services; and a switching fabric coupling compute elements in said set of compute elements. The set of network services includes firewall protection, Network Address Translation, Internet Protocol forwarding, bandwidth management, Secure Sockets Layer operations, Web caching, Web switching, and virtual private networking. Code operable on the compute elements enables the network services, and the compute elements are provided on blades which further include at least one input/output port.

Abstract: Methods and apparatus for transferring packets in a packet switched communication system. A system is provided that includes an L2 device including a controller determining for each packet received whether the received packet is to be inspected, an inspection device operable to inspect and filter packets identified by the controller including using a zone specific policy and an L2 controller for transferring inspected packets in accordance with L2 header information using L2 protocols.

Abstract: In general, the invention facilitates diagnosing fault conditions, such as flapping, by permitting users to request information for specific components in a network device such as a router. The invention also facilitates the diagnosis of other fault conditions, including, but not limited to, excessive numbers of dropped packets, hard drive crashes, high temperature readings, and inactive interface cards. A user may obtain a targeted log containing information relating to selected fault conditions or other network device events, rather than a system log containing information relating to all network device events, some of which may not be of interest to the user. The targeted log may be parsed and analyzed with greater ease than the system log.

Abstract: Techniques are described for selectively filtering data, such as network packets, that correspond to forwarding tables. For example, a router receives packets from an input interface of an interface card (IFC). The router applies one or more input interface filters associated with the input interface that received the packet. The router selectively associates the packet with a forwarding table, applies a corresponding forwarding filter, and determines the output interface corresponding to the next hop of the packet. The router may further apply one or more output interface filters associated with the output interface, and forwards the packet in accordance with the respective forwarding information.

Abstract: A communication network design circuit can derive a path and a necessary link capacity for multiple point communication service permitting arbitrary communication within a predetermined range of communication amount by providing traffic amount of data in-flowing through an ingress node and traffic amount of data flowing out through an egress node. The communication network designing circuit has setting means for setting a mathematical programming problem for deriving the multiple point communication service and optimizing means for solving the mathematical programming problem set by the setting means and obtaining the path for the multiple point communication service.

Abstract: A system for multicasting a packet of data to a single data stream is provided. The system may determine a size of the packet and may send a single copy of the packet if the size of the packet exceeds a threshold value. A number of copies of the packet yet to be multicast may be ascertained if the size of the packet of data does not exceed the threshold value. Copies of the packet may be transmitted based on the number of copies of the packet yet to be multicast.

Abstract: A network device includes an interface and packet processing logic. The interface receives a multicast packet. The packet processing logic determines identifier data corresponding to the received multicast packet and replicates the identifier data to multiple outgoing packet forward engines at a first point in a processing path. The packet processing logic further replicates the identifier data to multiple data streams at a second point in the processing path and replicates the identifier data to multiple logical interfaces in the same stream at a third point in the processing path.

Abstract: A network device is provided. The network device may include at least one set of buffers to buffer network traffic; a monitor to determine varying amounts of available buffer space associated with the buffers; and logic to assign reading rates to the respective buffers for scheduling output of the buffered traffic. The logic may be configured to increase an assigned reading rate associated with one of the buffers to at least one elevated reading rate based on a reduction of the available buffer space in the one buffer to a first amount and reset the at least one elevated reading rate to the assigned reading rate based on a subsequent increase in the available buffer space beyond that of the first amount.

Abstract: A node apparatus includes a header processing section (2) for determining an output destination of an incoming packet and a quality class from the header information of the packet, a route table (3), and a quality description table (4), and storing the packet in an output queue (6) determined by the determined output destination and quality class, an output control section (7) for reading out a packet from the output queue in accordance with the quality set for each output queue (6) and sending out the read packet through a VC determined by the determined output destination and quality class.